1. Field of the Invention
The present invention relates to radar and infrared sensor systems. More particularly, the present invention relates to radar transparencies used in radar and infrared sensor systems.
2. Background of the Invention
Advances in current missile defense initiatives include utilization and development of dual mode seekers employing both IR (infrared) and RF (radio frequency) sensors. Dual mode seekers provide the high resolution of a single mode IR seeker but, unlike single mode IR seekers, remain operative in adverse weather conditions such as rain, fog, or humidity. Thus, dual mode seekers satisfy mission profiles for both high altitude applications and low altitude applications (e.g., the low endo-atmosphere and below) where climatic conditions can inhibit IR performance. Moreover, dual mode seekers provide substantially improved target acquisition by combining both RF and IR signals and are generally less susceptible to electronic countermeasures.
Most approaches to dual mode seekers have involved separate radar transparencies for the RF and the IR sensors. For example, current dual mode radome developments have focused on radomes with inset windows for both IR and RF sensors or two separate radomes for the RF and IR components. While these configurations can satisfy some mission requirements, they have a significant impact on the missile system in terms of both seek configuration and missile kinematics, and preclude a simultaneous full field view by both sensors, thus degrading seeker performance.
Hence, there remains a need for a radar transparency which allows passage of both IR and RF radiation.